Commit 
7583b63c343c ("powerpc/40x: Remove STB03xxx") removes the config
STB03xxx, but left a reference in ./drivers/usb/Kconfig behind.
Hence, ./scripts/checkkconfigsymbols.py warns:
STB03xxx
Referencing files: drivers/usb/Kconfig
Remove this reference to the deleted config.
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Link: https://lore.kernel.org/r/20210818071137.22711-4-lukas.bulwahn@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 
 config USB_OHCI_LITTLE_ENDIAN
        bool
-       default n if STB03xxx || PPC_MPC52xx
+       default n if PPC_MPC52xx
        default y
 
 config USB_EHCI_BIG_ENDIAN_MMIO